Differentiating Phonetically and Phonologically Conditioned Sound Change

Josef Fruehwald, University of Pennsylvania
LSA, January 5, 2013

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Outline

Most sound changes exibit conditoning. Some sound changes appear to be conditioned.

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Phonetics and Phonology

Distinguishing the two

Is it possible to distinguish between phonetic effects (universial acoustic and/or gradient coarticulation) and categorical phonological selection? This is, of course, a long standing question. (e.g. Cohn, 1993; inter alia)

Diachrony and Phonology

An increasing number of phonologists point to diachronic sound change and the reanalysis of phonetic coarticulation as the source of phonological generalizations.

Phonologization

It has been proposed by various researchers that most phonological processes enter grammars as reanalyses of phonetic processes (Hyman, 1976), and it has been suggested that this process of phonologization is the source of phonological naturalness, and markedness (Blevins, 2004).

Phonologization as a gradual process.

  1. Variation strictly due to production/perception errors.
    • [up]; [ut] ~ [ʉt]
  2. Errors accumulate.
    • [up]; [ʉt] ~ [yt]
  3. Reanalysis as a phonological process.
    • u → y / _t

(Ohala, 1981)

Sociolinguistic Variation

In Philadelphia, sociolinguistic variation has been reported on for the pre-voiceless allophone of /ay/ (backing it indexes masculinity, and toughness (Conn, 2005; Wagner, 2007)), but not for other allophones of /ay/.

The pre-nasal allophones of /aw/ is markedly more raised and fronted, but has not exhibited sociolinguistic differentation distinct from other /aw/ allophones.

Proposal: This may be because /ay0/ is phonologically differentiated from /ay/, but /awN/ is a phonetic variant.

Gaps to Fill

Change in Progress

To my knowledge, phonologization has not been observed in progress.

Sociolinguistic Utilization

More sociolinguistic work is necessary to see if phonological allophones are utilized differently from phonetic variants.

Data

Philadelphia Neighborhood Corpus

Corpus Develoment
Data used here
  • Data from 308 White speakers.
  • Interviewed between 1973 and 2010.
  • Born between 1888 and 1991.

plot of chunk plot_speakers  

Case Studies

The effect of nasals on /aw/

plot of chunk plot_aw_means  

plot of chunk aw_smooth_plot  

aw awN total
6382 5494 11876

A following nasal favors the direction of the change.

Case Studies

The effect of /l/ on /ow/

plot of chunk plot_ow_means  

plot of chunk ow_smooth_plot  

ow owL total
5629 1946 7575

A following /l/ blocks fronting.

Case Studies

The effect of voiceless obstruents on /ay/

plot of chunk plot_ay_means  

plot of chunk ay_smooth_plot  

ay ay0 total
12131 18252 30383

/ay/ only raises pre-voiceless.

The Trajectories of Change

Background Assumption

Proposal

The Trajectories of Change

Phonological Differentiation

  • Phonology
    • VxVy/ _C
  • Phonology-Phonetics Interface
    • Vx → Low F2
    • Vy → Higher F2
plot of chunk assim

Targets are independent.

The Trajectories of Change

Phonetic Effect

  • Phonology
    • V
  • Phonology-Phonetics Interface
    • V → Low F2
  • Coarticulation/Gestural Phasing/Natural Acoustics
    • VC has a higher F2

plot of chunk coarticulation  

Target of VC is yoked to V.

The Trajectories of Change

Consequences

Phonological

The trajectories are independent.

Phonetic

The trajectories are necessarilly parallel.

The Trajectories of Change

Phonological
plot of chunk construct_assim

Divergent trajectories have different rates of change.

Phonetic
plot of chunk construct_coarticulate

Parallel trajectories have the same rate of change.

Trajectories of Change

The easiest way to test for parallelity is to fit straight lines for each variant, and compare the slopes. But, there are important non-linear patterns in these case studies.

plot of chunk replot_aw_means  

plot of chunk replot_ow_means  

plot of chunk replot_ay_means  

Moreover, we’d expect phonologization to exhibit trajectories that are initially parallel, but then diverge.

Modeling the Rate of Change

What I did instead was model the rate of change at ever year, in terms of the size of year-over-year changes.

Results

/aw/: Trajectory and Rate of Change Estimates

plot of chunk plot_aw_pred_delta  

  • [aw] is reliably fronting and raising
Women Men
1914
1915
  • [aw] fronting and raising peaks
Women Men
1949 1960
  • [aw] begins to lower and back, reversing the earlier change.
Women Men
1965

Results

/aw/: Rate of Change Differences

plot of chunk plot_aw_delta_diff
Conclusion

[aw] and [awN] do not have reliably different rates of change at any point during the 20th century, meaning their phonetic targets appear to be yoked together, even in the reversal of the change.

Results

/ow/: Trajectory and Rate of Change Estimates

Since men barely participated in this change, I’ll be looking exclusively at women.

plot of chunk plot_ow_pred_delta  

  • [ow] is reliably fronting.
    • 1906
  • [ow] fronting peaks
    • 1960
  • [ow] begins to back.
    • 1969

Results

/ow/: Rate of Change Differences

plot of chunk plot_ow_delta_diff
Conclusion
  • Earliest date of positive [ow] rate of change:
    • 1906
  • Earliest date of a reliable difference in [ow] and [owL] rate of change:
    • 1908

[owL] was categorically excluded from undergoing the change from its outset, making this a phonologicallty conditioned sound change.

Results

/ay/: Trajectory and Rate of Change Estimates

Due to weak sex differentiation, this analysis was pooled over men and women.

plot of chunk plot_ay_pred_delta  

  • [ay0] is reliably raising.
    • 1904
  • [ay0] raising peaks.
    • 1974

Results

/ay/: Rate of Change Differences

plot of chunk plot_ay_delta_diff
Conclusion
  • Earliest date of positive [ay0] rate of change:
    • 1904
  • Earliest date of a reliable difference in [ay] and [ay0] rate of change:
    • 1904

[ay0] was categorically excluded from undergoing the change from its outset, making this a phonologicallty conditioned sound change.

Conclusions

We have seen

We have not seen

Conclusions

By bringing together a model of the phonology-phonetics interface, and a theory of phonetic changes, we have produced a novel methodology for distinguishing between phonological and phonetic effects.

South Philadelphia Row Homes, 2012

Thanks!

References